Tumbling barrel



L. B. GREEN TUMBLING BARREL Jan. 30, 1934.

Filed May 5, 1930 Lee is. @86

Patented Jan. 30, 1934 UNETEQ STATES PATENT OFFICE TUMBLIN G BARREL Application May 3, 1930. Serial No. 449,674

5 Claims.

My invention relates to so called tumbling barrels as employed for cleaning, burnishing or polishing castings, and more particularly to tumbling barrels which have their axes inclined when in use, and which heretofore have commonly been built with their bottoms at right angles to their axes.

With a barrel bottom thus disposed, the plane of the bottom remains at a constant inclination during the rotation of the barrel, and the weight of the superposed castings presses the lowermost castings against the bottom to such an extent that the latter will not readily shift back and forth. Consequently, the castings adjacent to the barrel bottom will not be burnished or polished to anywhere near the same extent as the castings which were farther from this bottom.

To reduce this lack of uniformity in the eifect of the tumbling on different portions of a given batch of articles, tumbling barrels have frequently been constructed with tapering barrel sides as for example, frustro-conical or frustro-pyramida1but even this change in shape has not proven adequate for securing an approximately equal effect on the entire batch of castings or other objects within an inclined tumbling barrel. Ribs within an inclined barrel have also proven inadequate, for the reason that while such ribs will eiiect a greater movement of some portions of the barrel contents, other portions of the batch will catch on the ribs and will be carried around in closely packed masses without'receiving the needed relative movements needed for the intended finishing eifect.

For these reasons, those using inclined tumbling or burnishing barrels for many purposes, have heretofore found it necessary to sort out the adequately finished castings from the less finished ones and to subject the latter to an additional tumbling, thus considerably increasing the cost of the tumbling barrel operation.

My present invention aims to overcome the above recited inadequate operation of inclined tumbling barrel without materially increasing the cost of the barrels and by an exceedingly simple change in the construction of the barrel, namely by providing such a barrel with a bottom formed and disposed for shifting of the castings adjacent to the barrel bottom positively and to a substantially equal extent with the relatively higher castings in the barrel, thereby securing an approximately equal tumbling effect on the entire batch and eliminating the need of a second treatment of part of the batch.

More particularly, my invention aims to provide an inclined tumbling barrel in which the inclination of any given part of the inward face of the barrel bottom will change to a considerable extent during each revolution of the barrel, thereby materially enhancing the shifting of the lower portions of the barrel content during the rotation of the barrel.

Furthermore, my invention aims to provide a construction which can easily be adapted at little or no increase in cost to common types of inclined tumbling barrels, regardless of the shape and relative disposition of the barrel sides or of the inclination at which the axis of the barrel is to be disposed when in use.

Still further and also more detailed objects will appear from the following specification and from the accompanying drawing, in which Fig. 1 is a central and vertical section through a tumbling barrel embodying my invention and through adjacent parts of the tumbling device of which this barrel forms a part, and through a batch of material in the barrel, showing the barrel in the position in which the upper face of its bottom is at the greatest inclination to the horizontal.

Fig. 2 is a similar section, taken after the barrel has been rotated a half turn.

Fig. 3 is a section taken along the line 3-3 of Fig. 2.

Fig. 4 is a central and vertical section through a tumbling barrel having its bottom in the heretofore customary position, showing the disposition of a batch of material in the barrel.

Fig. 5 is a central and vertical section through a hexagonal tumbling barrel embodying my invention and having an upwardly concaved bottom.

Figure 6 is a modification of the barrel disclosed in Figure 1, wherein the bottom of the barrel is formed by a curved surface, the radius of which lies at an angle to the axis of the barrel.

Illustrative of my invention, Fig. 1 shows a tumbling barrel comprising a frustro-conical tubular barrel portion 1 and a bottom 2 fastened to the larger end of this barrel portion. This barrel is also fastened, as by screws 3, to a hub 4 on the upper end of an inclined shaft 5 by which the tumbling barrel is rotated when in operation. The bottom 2 has its upper face 2A oblique to the axis A of the tubular barrel portion 1, and hence inclined with respect to a plane at right angles to the said axis A.

When the common axis A of the shaft 5 and the tumbling barrel is maintained at a fixed inclination to the vertical during a rotation of the tumbling barrel, the inclination of the upper or inward face 2A of the barrel bottom changes continuously during each rotation of the tumbling barrel, namely from the steep inclination shown in full lines in Fig. 1 to the lesser inclination shown for this face in Fig. 2. In practice this change in the bottom inclination has a decided effect in shifting and redistributing the contents of the tumbling barrel, since it shifts portions of the material radially of the barrel along the barrel bottom and also varies the extent to which the material approaches the mouth end. of the barrel.

In a similarly shaped tumbling barrel of the heretofore customary type in which the bottom has its upper face at right angles to the axis of the barrel, as illustrated in Fig. i, a charge of castings 9A just sufiicient to cover the entire bottom 8 of the barrel will distribute itself so that the top 9 of the charge remains in an approximately constant plane. A half rotation of the barrel would tend to shift this outward face of the batch of castings to the plane 10, but the portions of the castings which are not near the bottom 8 will roll and shift out of their former positions during the rotating of the barrel and always tend to present the outward face of the batch of castings in the same plane 10. However, the castings adjacent to the bottom 8 will be pressed against this bottom by the weight of the castings above them, so that the bottom layer or layers of the castings receive but little relative movement, so that these castings are not cleaned, smoothed or burnished by rubbing against one another.

With the upper face 2A of the barrel bottom oblique to the axis A of the barrel, this inward face of the barrel bottom becomes more steeply inclined as the barrel rotates from the position of Fig. 2 to that of Fig. 1. Consequently, during every such half-turn, gravity will tend to slide a portion of the castings along the barrel bottom toward the axis of the barrel, thereby causing these castings to redistribute themselves and to approach nearer to the mouth of the barrel as shown in Fig. 1.

Moreover, during the rotation of my tumbling barrel, the angle at which the upper face of the barrel bottom is inclined (with respect to a horizontal plane) continuously changes back and forth between the extreme positions shown in Fig. 1; and when the said bottom face is at or near its most steeply inclined position of Fig. 1, the material will be higher near the mouth end of the barrel than adjacent to the bottom, so that some of the higher material will roll down toward the barrel bottom.

Likewise, when the barrel is at or near the other extreme position of Fig. 2 (in which the upper face of the barrel bottom has its minimum inclination to the horizontal), the material will be higher near this bottom than near the open end of the barrel, so that some of the upper particles adjacent to the said bottom will roll down toward the open end of the barrel. Consequently, my barrel continually changes the particles which are in contact with the barrel bottom. This action, which will not occur in an inclined tumbling barrel if the latter has its bottom at right angle to the axis of the barrel, is further enhanced by my tapering the barrel upwardly; and for the best effects, both the angles of conicity of the shell and the angle at which the upper face of the barrel bottom is tilted with respect to a plane atright angles to the axis of the shell should be less than the angle at which the axis of the barrel is inclined to a horizontal plane.

In practice, the combination of these gravityactuated movements with the rotation of the barrel causes a considerable share of the castings to tumble over one another, and the momentum. of some of these castings will carry them toward the mouth of the barrel to such an extent that the momentary upper face of the batch may slope upwards beyond a horizontal plane 11, as shown in Fig. 1, when the barrel is halted in that rotational position.

In other words, the batch of castings not only shifts along the bottom of the barrel so that a part of the upper face 2A of this bottom may be exposed in one rotational position of the barrel (as shown in Figs. 1 and 5), while the entire bottcm is covered with castings in the diametricaily opposite rotational position of Fig. 2, but also shifts the batch toward and away from the south of the barrel.

These actions supplement the tumbling effect obtained by using the ordinary barrel of Fig. 4 to such an extent that I can readily secure a fair- 1y uniform action on the entire constituents of a batch of castings, thereby avoiding the necessity of sorting out the inadequately finished castings and subjecting these latter castings to a second. tumbling operation.

However, while I have heretofore described my novel tumbling barrel in an embodiment in which the bore of the barrel portion is of circular section and in which the barrel bottom has a flat inward face, I do not wish to be limited to these or other details of the construction and arrangement thus disclosed. Obviously, many changes might be made without departing either from the spirit of my invention or from the appended claims.

For example, in the embodiment of Fig. 6; the barrel portion 12 of my tumbling barrel is hexagcnal and the bottom 13 is upwardly concaved, being a portion of a cylindrical surface which has its axis 14 offset laterally from the axis 15 of the barrel.

I also do not wish to be limited as to the purposes for which my tumbling barrel is employed, it being understood that the term castings as here used may designate the constituents of any batch of goods that are to be finished, and may also include the leather scraps, sawdust, abrasive or the like as commonly tumbled in the barrel along with such a batch of goods.

I claim as my invention:

1. A tumbling or burnishing barrel comprising a material-supporting bottom and a tubular side walls for confining the material on said bottom. and means for supporting the barrel to rotate on an inclined axis, so that the material is conjointly supported at all times by the said bottom and a portion of the said side wall; the tubular body having its axis coaxial with the axis of rotation of the barrel and the top material-supporting face of the bottom being disposed obliquely to both the axis of rotation of the barrel and the axis of the tubular side wall and assuming different angles of inclination to both axes on the rotation of the barrel.

2. A tumbling or burnishing barrel comprising a material supporting bottom and an upwardly open tubular side wall for confining the material on said bottom, and a rotatable shaft supporting the barrel; said shaft and tubular side wall having a common axis disposed at an inclination to a horizontal plane; and the top materialsupporting face of the bottom being disposed obliquely to the said common axis and assuming different angles of inclination to the said plane during the rotation of the barrel on said axis, whereby the said change of inclination of the barrel bottom causes the material in the barrel to shift toward the open end of the said side wall.

3. A tumbling or burnishing appliance for rotation about an inclined axis, comprising an upwardly open frusto-conical tubular casing having each end thereof in a plane at right angles to the axis of the casing, and a bottom member mounted in the lower end of the casing, the bottom member comprising a plate extending across the area of the casing at an angle of not less than 60 degrees and not more than 75 degrees to the axis of the casing, and a tubular flange integral with the said plate and extending within the casing downwardly from the peripheral portion of the said plate, the said flange reaching to the bottom of the casing and decreasing continuously in height from one side of the flange to the diametrically opposite side, and means securing the flange to the casing.

l. A tumbling or burnishing barrel for rotation about an inclined axis, comprising an upwardly open and upwardly tapering frusto-conical tubular shell coaxial with the said axis of rotation and presenting the upper end of the shell in a plane at right angles to the said axis, and a bottom member secured to and closing the lower end of the said shell and presenting its upper face in a second plane oblique to the first named plane; the angle between the said two planes and the angle of conicity of the said shell being each not greater than the angle at which the axis of rotation is inclined with reference to a horizontal plane, whereby the taper of the shell cooperates with the said obliquity of the upper face of the bottom member to cause the upper face of material in the barrel to Vary in its inclination to the said axis during each rotation of the barrel so as to cause part of the upper face portion of the material to roll longitudinally of the barrel upon lower parts of material.

5. A tumbling or burnishing appliance for rotation about an inclined axis, comprising an upwardly tapering and upwardly open frustroconical tubular shell having each end thereof in a plane at right angles to the axis of the shell, and a bottom member mounted in the lower end of the shell; the bottom member comprising a plate extending across the bore of the shell at an oblique angle to the axis of the shell, and a tubular flange integral with the said plate and extending within the shell downwardly from the peripheral portion of the said plate, the said flange reaching to the bottom of the shell and decreasing continuously in height from one side of the flange to the diametrically opposite side; and means securing the flange to the shell.

LEE B. GREEN.

It G0 TLTE 

